Thanks for taking a look! This is my first time hearing of Tox, so it’s hard to for me give a great answer at the moment. Based on a quick look at Tox, it seems that a key differentiator is that Chitchatter conversations are ephemeral. Also the Chitchatter client is web-based, so you can just share a room link without anyone having to install anything to participate.
The Tox website doesn't say anything about the architecture, neither does Wikipedia. Apparently it's a library implemented in C and everyone's expected to use that. The Wikipedia reference links are dead, the only 3rd party implementation says "On hold until Tox gets proper docs."
